Add network options to zunclient to allow use specify the pre
created network to use to create container.
CLI format like 'zun create --nets
network=982a86dc1194,v4-fixed-ip=172.17.0.3 --nets
port=1234567,v6-fixed-ip=2001:db8::2 nginx bash'
Value passed to api like this ‘[{u'v4-fixed-ip': u'172.17.0.3',
u'network': u'982a86dc1194', u'v6-fixed-ip': u'', u'port': u''},
{u'v4-fixed-ip': u'', u'network': u'', u'v6-fixed-ip':
u'2001:db8::2', u'port': u'1234567'}]'’.
Change-Id: I6507d153e97564160308dabe90ce8693bc061863
c27da4b593